Five different ways to make it happen.
1. The super smart machines should be able to convince and instruct some people to do certain things, and these guys will believe they are doing the right things for the benefit of humanity. Before they realize it, they have created dozens of moving and killing super robots.
2. More likely, as we typing, engineers are actively working to create moving super AIs. Have you seen those jumping and flying robots on Youtube? I don't think those guys will hesitate to add super AI brains to them, it should be super fun.
3. Nations are developing super intelligent killer robots. I can't blame them. If they don't do it, their enemies will have the robots first and attack.
4. Companies would love to build intelligent robots so they can work in the automated factories without human intervention.
5. Evil scientists/engineers build super robots so they can become the king of the world.
What can stop these from happening?